Int J Sports Med 2002; 23(7): 489-494
DOI: 10.1055/s-2002-35069
Physiology & Biochemistry

© Georg Thieme Verlag Stuttgart · New York

Evidence of Exercise-Induced Cardiac Dysfunction and Elevated cTnT in Separate Cohorts Competing in an Ultra-Endurance Mountain Marathon Race

R.  E.  Shave 1 , E.  Dawson 2 , G.  Whyte 1 , K.  George 2 , D.  Ball 2 , D.  C.  Gaze 3 , P.  O.  Collinson 3
  • 1 British Olympic Medical Centre, Northwick Park Hospital, Harrow, Middlesex, UK
  • 2 Dept. of Exercise and Sports Science, Manchester Metropolitan University, Alsager, UK
  • 3 Dept. of Chemical Pathology, St.George's Hospital Medical School, UK
Further Information

Publication History

Accepted after revision: April 6, 2002

Publication Date:
28 October 2002 (online)

Abstract

Cardiac damage has recently been implicated in the aetiology of “exercise induced cardiac dysfunction”. The humoral markers of cardiac damage that have been utilised to date are not sufficiently cardio-specific to investigate this hypothesis. The aim of the present study was to examine cardiac function following prolonged exercise, and investigate the contention of cardiac damage utilising a new highly cardio-specific marker. Thirty-seven competitors in the 2-day Lowe Alpine Mountain Marathon 2000 volunteered for the study. Competitors were sub-divided into 2 groups. Group 1 (n = 11) were examined using echocardiography pre and post the event, examining left ventricular diastolic and systolic function. Group 2 (n = 26) had venous blood samples drawn prior to the event and immediately following day-1 and day-2. Blood samples were analysed for total creatine kinase activity (CK), creatine kinase isoenzyme MBmass (CK-MBmass), and cardiac troponin T. Echocardiographic results indicated left ventricular diastolic and systolic dysfunction following cessation of exercise. CK and CK-MBmass were both elevated following day-1, and immediately following race completion. Cardiac troponin T levels were below the 99th percentile (0.01 µg/L) in all subjects prior to the event, following day-1 cTnT was elevated above 0.01 µg/L in 13 subjects, but returned to below 0.01 µg/L following race completion on day-2. However, no individual data reached clinical cut-off levels for acute myocardial infarction (AMI) (0.1 µg/L). Two days arduous exercise over mountainous terrain resulted in cardiac dysfunction, and significant skeletal muscular degradation. The elevation of cTnT above the 99th percentile in the present study is suggestive of minimal myocardial damage. The clinical significance of and exact mechanism responsible for such damage remains to be elucidated.

References

R. E. Shave

British Olympic Medical Centre · Northwick Park Hospital

Watford Rd · Harrow · Middlesex, HA1 3UJ · UK

Fax: + 44-208-8648738

Email: robert.shave@boa.org.uk